LPT3 Should Be LPT1



I have a new computer with an ASUS P5N32-SLI motherboard. This motherboard
has no physical parallel ports at all. It seems to be a new trend. XP Pro
was installed. I now need an LPT1 to interface to some speciallized IC
programming equipment, so I added a MosChip Technoloy SY-PIO9835-2S1P PCI
card which has 2 COM ports and 1 LPT port. When installation was complete,
the parallel port was added as LPT3. The specialized hardware cannot
communicate on LPT3, so I need this physical parallel port to be reinstalled
as LPT1. In the Device Manager under Ports (COM & LPT), only COM1, LPT3,
COM3, and COM4 exist. The latter 3 are from the MosChip Technology PCI card.
LPT3 cannot be changed to LPT1 on the resources tab because the "Setting
Based ON", "Use Automatic Settings", and "Change Settings" controls are all
greyed out and inoperative. Is this because all 3 LPT ports are though to
exist already, so you can't change one? Under Printers and FAXs, the
properties for any given printer allows assignement to any of the 3 parallel
ports LPT1, LPT2, and LPT3. This suggests Windows thinks they exist. A
regedit search of the registry keys shows that all 3 LPT ports are listed
under HKEY_LOCAL_MACHINE >> Software >> Microsoft >> Windows NT >> Currect
Version >> Ports. I do not know why LPT1 and LPT2 are listed here if they do
not exist. Is this why the fisrt real LPT port installed itself as LPT3?
How should I correct this? Should I uninstall LPT3, then delete the LPT1 and
LPT2 registry keys from the registry location above, and lastly reinstall the
new physical LPT port? Will this make it come up as LPT1? Are there any
downside risks or considerations to doing this? Thanks.


In the port's properties from device manager, do you not have an option to
change LPT port number on the "Port Settings" tab?


No. However, I have even tried one that did and checked with a number of
manufacturers who have the most configurability (including tech support at
www.lavalink.com and and www.cablemax.com (sold thru USBGear and SerialGear)
(LPT-1284-LP, 159548, 158343, etc.)).

Since the time I posted this I have found that as of XP, Microsoft no longer
supports fully featured LPT or COM ports. According to Microsoft's article:
"Legacy I/O Removal to Advance the PC Architecture", the ability to have
IRQs, DMAs, and I/O address ranges is part of the intentional abandonment of
anything having to do with ISA architecture. This is for the embetterment of
humanity by "Removal of obsolete, slow, complicated, and often poorly
understood interfaces offer[ing] obvious benefits toward this end: simpler,
more robust machines, and a lower cost of goods." From what I can gather,
the plan is for abandonment to become more guaranteed by Vista and its

My hypothesis is this: When COM and LPT ports are built into the
motherboard, the designers have the ability (at least for now) to add special
hardware and software in the BIOS that may still allow these ports to operate
in a relatively fully featured way. However, if you happen to have a
motherboard without them and try to add them with a PCI card, it will no
longer be possible (as of XP) to have any fully featured ones on your
computer, so just get over it. It takes about 2 person-months of labor to
reconstruct my development environment on a new machine.

Of course, this leaves me with very expensive development systems for
electronics and ICs which I can no longer support with Microsoft. I'm hoping
some creative soul has come up with some viable alternative, but judging from
what I've seen in many days of internet searches, there is no commercially
available solution.

I hope and pray someone truly proves me wrong.

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